1. Field of the Invention
The present invention relates to an optical transceiver having an MDIO interface.
2. Related Background Art
Patent Literature 1 describes an optical transceiver with an MDIO Management Data Input/Output) interface. The optical transceiver described in Patent Literature 1 is connected to an external upper layer (host device). The optical transceiver has a microcomputer and a logic device. The logic device is connected through an MDIO bus to the upper layer and connected through a parallel communication bus to the microcomputer. The microcomputer monitors an internal state of the optical transceiver. The microcomputer has an MDIO register set for storing a plurality of single data blocks indicative of the internal state of the optical transceiver and the prescribed information necessary for monitoring and controlling by the external upper layer. The logic device acquires through the parallel communication bus a single data block stored in the MDIO register set. A position (address) of each single data block stored among a plurality of registers in the MDIO register set is preliminarily determined depending upon a content of the single data blocks. The address of the MDIO register is specified by address information transmitted through the MDIO bus from the upper layer. The upper layer performs reading/writing of a single data block from or into the MDIO register specified by the address information, through the logic device.
Patent Literature 2 describes a communication device with a plurality of devices and a control device. The control device receives MDIO communication data from an external device. The control device refers to “ADDRESS” indicative of a destination of the communication data. When “ADDRESS” indicates a device conforming with the MDIO communication protocol, the control device transmits the MDIO communication data to the target device by use of the MDIO communication protocol. When “ADDRESS” indicates a device conforming with the SPI communication protocol, the control device transmits the SPI communication data to the target device by use of the SPI communication protocol.
Patent Literature 1: Japanese Patent Application Laid-Open Publication No. 2012-169745
Patent Literature 2: Japanese Patent Application Laid-Open Publication No. 2012-49812